The present invention relates to a compression device which compresses a moving image using a Moving Picture Experts Group (MPEG) method or the like, and an imaging device using the same.
In a conventional MPEG-4 compression (or encoding)/decompression (or decoding) device, the entire encoding/decoding is performed by hardware.
In the case where the entire encoding/decoding is performed by hardware, the circuit scale is necessarily increased, whereby reduction of the IC size is hindered. If such a device is applied to a portable instrument such as a portable telephone, a demand for reduction of the size of the instrument cannot be satisfied.
In the case where the entire encoding/decoding is performed by software, the load imposed on the CPU increases. Therefore, since the time necessary for the CPU to perform other processing is limited, the performance of the instrument cannot be realized. Moreover, since the operation time of the CPU increases, power consumption is increased. If such a device is applied to a portable instrument such as a portable telephone, a demand for reduction of power consumption in order to maintain battery life cannot be satisfied.